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4 years ago

WILL GIVE BRAINLIEST!!!

Mathematics

1 answer:

mamaluj [8]4 years ago

4 0

Answer:

87 points

Step-by-step explanation:

lets take "x" as the avg test scores of the past 6 tests

since their are 6 tests, we would represent the 6 tests as "6x"

to find average we need to add all numbers, and divide by the number of numbers

so since the final exam counts as two tests we need to add "99" twice

(6x+99+99)/8=90

multiply by "8" on bots sides and add 99 and 99 together

6x+198=720

subtract 198

6x=522

divide by 6

x=87

hope this helps

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Step-by-step explanation:

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(a)

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Answer:

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Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Algebra I

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Step-by-step explanation:

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